1 /*
2  * bitmaps.c --- routines to read, write, and manipulate the inode and
3  * block bitmaps.
4  *
5  * Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o.
6  *
7  * %Begin-Header%
8  * This file may be redistributed under the terms of the GNU Library
9  * General Public License, version 2.
10  * %End-Header%
11  */
12 
13 #include <stdio.h>
14 #include <string.h>
15 #if HAVE_UNISTD_H
16 #include <unistd.h>
17 #endif
18 #include <fcntl.h>
19 #include <time.h>
20 #if HAVE_SYS_STAT_H
21 #include <sys/stat.h>
22 #endif
23 #if HAVE_SYS_TYPES_H
24 #include <sys/types.h>
25 #endif
26 
27 #include "ext2_fs.h"
28 #include "ext2fs.h"
29 #include "ext2fsP.h"
30 #include "bmap64.h"
31 
ext2fs_free_inode_bitmap(ext2fs_inode_bitmap bitmap)32 void ext2fs_free_inode_bitmap(ext2fs_inode_bitmap bitmap)
33 {
34 	ext2fs_free_generic_bmap(bitmap);
35 }
36 
ext2fs_free_block_bitmap(ext2fs_block_bitmap bitmap)37 void ext2fs_free_block_bitmap(ext2fs_block_bitmap bitmap)
38 {
39 	ext2fs_free_generic_bmap(bitmap);
40 }
41 
ext2fs_copy_bitmap(ext2fs_generic_bitmap src,ext2fs_generic_bitmap * dest)42 errcode_t ext2fs_copy_bitmap(ext2fs_generic_bitmap src,
43 			     ext2fs_generic_bitmap *dest)
44 {
45 	return (ext2fs_copy_generic_bmap(src, dest));
46 }
ext2fs_set_bitmap_padding(ext2fs_generic_bitmap map)47 void ext2fs_set_bitmap_padding(ext2fs_generic_bitmap map)
48 {
49 	ext2fs_set_generic_bmap_padding(map);
50 }
51 
ext2fs_allocate_inode_bitmap(ext2_filsys fs,const char * descr,ext2fs_inode_bitmap * ret)52 errcode_t ext2fs_allocate_inode_bitmap(ext2_filsys fs,
53 				       const char *descr,
54 				       ext2fs_inode_bitmap *ret)
55 {
56 	__u64		start, end, real_end;
57 
58 	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
59 
60 	fs->write_bitmaps = ext2fs_write_bitmaps;
61 
62 	start = 1;
63 	end = fs->super->s_inodes_count;
64 	real_end = (EXT2_INODES_PER_GROUP(fs->super) * fs->group_desc_count);
65 
66 	/* Are we permitted to use new-style bitmaps? */
67 	if (fs->flags & EXT2_FLAG_64BITS)
68 		return (ext2fs_alloc_generic_bmap(fs,
69 				EXT2_ET_MAGIC_INODE_BITMAP64,
70 				fs->default_bitmap_type,
71 				start, end, real_end, descr, ret));
72 
73 	/* Otherwise, check to see if the file system is small enough
74 	 * to use old-style 32-bit bitmaps */
75 	if ((end > ~0U) || (real_end > ~0U))
76 		return EXT2_ET_CANT_USE_LEGACY_BITMAPS;
77 
78 	return (ext2fs_make_generic_bitmap(EXT2_ET_MAGIC_INODE_BITMAP, fs,
79 					 start, end, real_end,
80 					 descr, 0,
81 					 (ext2fs_generic_bitmap *) ret));
82 }
83 
ext2fs_allocate_block_bitmap(ext2_filsys fs,const char * descr,ext2fs_block_bitmap * ret)84 errcode_t ext2fs_allocate_block_bitmap(ext2_filsys fs,
85 				       const char *descr,
86 				       ext2fs_block_bitmap *ret)
87 {
88 	__u64		start, end, real_end;
89 
90 	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
91 
92 	fs->write_bitmaps = ext2fs_write_bitmaps;
93 
94 	start = EXT2FS_B2C(fs, fs->super->s_first_data_block);
95 	end = EXT2FS_B2C(fs, ext2fs_blocks_count(fs->super)-1);
96 	real_end = ((__u64) EXT2_CLUSTERS_PER_GROUP(fs->super)
97 		    * (__u64) fs->group_desc_count)-1 + start;
98 
99 	if (fs->flags & EXT2_FLAG_64BITS)
100 		return (ext2fs_alloc_generic_bmap(fs,
101 				EXT2_ET_MAGIC_BLOCK_BITMAP64,
102 				fs->default_bitmap_type,
103 				start, end, real_end, descr, ret));
104 
105 	if ((end > ~0U) || (real_end > ~0U))
106 		return EXT2_ET_CANT_USE_LEGACY_BITMAPS;
107 
108 	return (ext2fs_make_generic_bitmap(EXT2_ET_MAGIC_BLOCK_BITMAP, fs,
109 					   start, end, real_end,
110 					   descr, 0,
111 					   (ext2fs_generic_bitmap *) ret));
112 }
113 
114 /*
115  * ext2fs_allocate_block_bitmap() really allocates a per-cluster
116  * bitmap for backwards compatibility.  This function allocates a
117  * block bitmap which is truly per-block, even if clusters/bigalloc
118  * are enabled.  mke2fs and e2fsck need this for tracking the
119  * allocation of the file system metadata blocks.
120  */
ext2fs_allocate_subcluster_bitmap(ext2_filsys fs,const char * descr,ext2fs_block_bitmap * ret)121 errcode_t ext2fs_allocate_subcluster_bitmap(ext2_filsys fs,
122 					    const char *descr,
123 					    ext2fs_block_bitmap *ret)
124 {
125 	__u64			start, end, real_end;
126 	ext2fs_generic_bitmap	bmap;
127 	errcode_t		retval;
128 
129 	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
130 
131 	fs->write_bitmaps = ext2fs_write_bitmaps;
132 
133 	if (!fs->cluster_ratio_bits)
134 		return ext2fs_allocate_block_bitmap(fs, descr, ret);
135 
136 	if ((fs->flags & EXT2_FLAG_64BITS) == 0)
137 		return EXT2_ET_CANT_USE_LEGACY_BITMAPS;
138 
139 	start = fs->super->s_first_data_block;
140 	end = ext2fs_blocks_count(fs->super)-1;
141 	real_end = ((__u64) EXT2_BLOCKS_PER_GROUP(fs->super)
142 		    * (__u64) fs->group_desc_count)-1 + start;
143 
144 	retval = ext2fs_alloc_generic_bmap(fs, EXT2_ET_MAGIC_BLOCK_BITMAP64,
145 					   fs->default_bitmap_type, start,
146 					   end, real_end, descr, &bmap);
147 	if (retval)
148 		return retval;
149 	bmap->cluster_bits = 0;
150 	*ret = bmap;
151 	return 0;
152 }
153 
ext2fs_get_bitmap_granularity(ext2fs_block_bitmap bitmap)154 int ext2fs_get_bitmap_granularity(ext2fs_block_bitmap bitmap)
155 {
156 	ext2fs_generic_bitmap bmap = bitmap;
157 
158 	if (!EXT2FS_IS_64_BITMAP(bmap))
159 		return 0;
160 
161 	return bmap->cluster_bits;
162 }
163 
ext2fs_fudge_inode_bitmap_end(ext2fs_inode_bitmap bitmap,ext2_ino_t end,ext2_ino_t * oend)164 errcode_t ext2fs_fudge_inode_bitmap_end(ext2fs_inode_bitmap bitmap,
165 					ext2_ino_t end, ext2_ino_t *oend)
166 {
167 	__u64 tmp_oend;
168 	int retval;
169 
170 	retval = ext2fs_fudge_generic_bmap_end((ext2fs_generic_bitmap) bitmap,
171 					       EXT2_ET_FUDGE_INODE_BITMAP_END,
172 					       end, &tmp_oend);
173 	if (oend)
174 		*oend = tmp_oend;
175 	return retval;
176 }
177 
ext2fs_fudge_block_bitmap_end(ext2fs_block_bitmap bitmap,blk_t end,blk_t * oend)178 errcode_t ext2fs_fudge_block_bitmap_end(ext2fs_block_bitmap bitmap,
179 					blk_t end, blk_t *oend)
180 {
181 	return (ext2fs_fudge_generic_bitmap_end(bitmap,
182 						EXT2_ET_MAGIC_BLOCK_BITMAP,
183 						EXT2_ET_FUDGE_BLOCK_BITMAP_END,
184 						end, oend));
185 }
186 
ext2fs_fudge_block_bitmap_end2(ext2fs_block_bitmap bitmap,blk64_t end,blk64_t * oend)187 errcode_t ext2fs_fudge_block_bitmap_end2(ext2fs_block_bitmap bitmap,
188 					 blk64_t end, blk64_t *oend)
189 {
190 	return (ext2fs_fudge_generic_bmap_end(bitmap,
191 					      EXT2_ET_FUDGE_BLOCK_BITMAP_END,
192 					      end, oend));
193 }
194 
ext2fs_clear_inode_bitmap(ext2fs_inode_bitmap bitmap)195 void ext2fs_clear_inode_bitmap(ext2fs_inode_bitmap bitmap)
196 {
197 	ext2fs_clear_generic_bmap(bitmap);
198 }
199 
ext2fs_clear_block_bitmap(ext2fs_block_bitmap bitmap)200 void ext2fs_clear_block_bitmap(ext2fs_block_bitmap bitmap)
201 {
202 	ext2fs_clear_generic_bmap(bitmap);
203 }
204 
ext2fs_resize_inode_bitmap(__u32 new_end,__u32 new_real_end,ext2fs_inode_bitmap bmap)205 errcode_t ext2fs_resize_inode_bitmap(__u32 new_end, __u32 new_real_end,
206 				     ext2fs_inode_bitmap bmap)
207 {
208 	return (ext2fs_resize_generic_bitmap(EXT2_ET_MAGIC_INODE_BITMAP,
209 					     new_end, new_real_end, bmap));
210 }
211 
ext2fs_resize_inode_bitmap2(__u64 new_end,__u64 new_real_end,ext2fs_inode_bitmap bmap)212 errcode_t ext2fs_resize_inode_bitmap2(__u64 new_end, __u64 new_real_end,
213 				      ext2fs_inode_bitmap bmap)
214 {
215 	return (ext2fs_resize_generic_bmap(bmap, new_end, new_real_end));
216 }
217 
ext2fs_resize_block_bitmap(__u32 new_end,__u32 new_real_end,ext2fs_block_bitmap bmap)218 errcode_t ext2fs_resize_block_bitmap(__u32 new_end, __u32 new_real_end,
219 				     ext2fs_block_bitmap bmap)
220 {
221 	return (ext2fs_resize_generic_bitmap(EXT2_ET_MAGIC_BLOCK_BITMAP,
222 					     new_end, new_real_end, bmap));
223 }
224 
ext2fs_resize_block_bitmap2(__u64 new_end,__u64 new_real_end,ext2fs_block_bitmap bmap)225 errcode_t ext2fs_resize_block_bitmap2(__u64 new_end, __u64 new_real_end,
226 				      ext2fs_block_bitmap bmap)
227 {
228 	return (ext2fs_resize_generic_bmap(bmap, new_end, new_real_end));
229 }
230 
ext2fs_compare_block_bitmap(ext2fs_block_bitmap bm1,ext2fs_block_bitmap bm2)231 errcode_t ext2fs_compare_block_bitmap(ext2fs_block_bitmap bm1,
232 				      ext2fs_block_bitmap bm2)
233 {
234 	return (ext2fs_compare_generic_bmap(EXT2_ET_NEQ_BLOCK_BITMAP,
235 					    bm1, bm2));
236 }
237 
ext2fs_compare_inode_bitmap(ext2fs_inode_bitmap bm1,ext2fs_inode_bitmap bm2)238 errcode_t ext2fs_compare_inode_bitmap(ext2fs_inode_bitmap bm1,
239 				      ext2fs_inode_bitmap bm2)
240 {
241 	return (ext2fs_compare_generic_bmap(EXT2_ET_NEQ_INODE_BITMAP,
242 					    bm1, bm2));
243 }
244 
ext2fs_set_inode_bitmap_range(ext2fs_inode_bitmap bmap,ext2_ino_t start,unsigned int num,void * in)245 errcode_t ext2fs_set_inode_bitmap_range(ext2fs_inode_bitmap bmap,
246 					ext2_ino_t start, unsigned int num,
247 					void *in)
248 {
249 	return (ext2fs_set_generic_bitmap_range(bmap,
250 						EXT2_ET_MAGIC_INODE_BITMAP,
251 						start, num, in));
252 }
253 
ext2fs_set_inode_bitmap_range2(ext2fs_inode_bitmap bmap,__u64 start,size_t num,void * in)254 errcode_t ext2fs_set_inode_bitmap_range2(ext2fs_inode_bitmap bmap,
255 					 __u64 start, size_t num,
256 					 void *in)
257 {
258 	return (ext2fs_set_generic_bmap_range(bmap, start, num, in));
259 }
260 
ext2fs_get_inode_bitmap_range(ext2fs_inode_bitmap bmap,ext2_ino_t start,unsigned int num,void * out)261 errcode_t ext2fs_get_inode_bitmap_range(ext2fs_inode_bitmap bmap,
262 					ext2_ino_t start, unsigned int num,
263 					void *out)
264 {
265 	return (ext2fs_get_generic_bitmap_range(bmap,
266 						EXT2_ET_MAGIC_INODE_BITMAP,
267 						start, num, out));
268 }
269 
ext2fs_get_inode_bitmap_range2(ext2fs_inode_bitmap bmap,__u64 start,size_t num,void * out)270 errcode_t ext2fs_get_inode_bitmap_range2(ext2fs_inode_bitmap bmap,
271 					 __u64 start, size_t num,
272 					 void *out)
273 {
274 	return (ext2fs_get_generic_bmap_range(bmap, start, num, out));
275 }
276 
ext2fs_set_block_bitmap_range(ext2fs_block_bitmap bmap,blk_t start,unsigned int num,void * in)277 errcode_t ext2fs_set_block_bitmap_range(ext2fs_block_bitmap bmap,
278 					blk_t start, unsigned int num,
279 					void *in)
280 {
281 	return (ext2fs_set_generic_bitmap_range(bmap,
282 						EXT2_ET_MAGIC_BLOCK_BITMAP,
283 						start, num, in));
284 }
285 
ext2fs_set_block_bitmap_range2(ext2fs_block_bitmap bmap,blk64_t start,size_t num,void * in)286 errcode_t ext2fs_set_block_bitmap_range2(ext2fs_block_bitmap bmap,
287 					 blk64_t start, size_t num,
288 					 void *in)
289 {
290 	return (ext2fs_set_generic_bmap_range(bmap, start, num, in));
291 }
292 
ext2fs_get_block_bitmap_range(ext2fs_block_bitmap bmap,blk_t start,unsigned int num,void * out)293 errcode_t ext2fs_get_block_bitmap_range(ext2fs_block_bitmap bmap,
294 					blk_t start, unsigned int num,
295 					void *out)
296 {
297 	return (ext2fs_get_generic_bitmap_range(bmap,
298 						EXT2_ET_MAGIC_BLOCK_BITMAP,
299 						start, num, out));
300 }
301 
ext2fs_get_block_bitmap_range2(ext2fs_block_bitmap bmap,blk64_t start,size_t num,void * out)302 errcode_t ext2fs_get_block_bitmap_range2(ext2fs_block_bitmap bmap,
303 					 blk64_t start, size_t num,
304 					 void *out)
305 {
306 	return (ext2fs_get_generic_bmap_range(bmap, start, num, out));
307 }
308